20 Minute C-11, 10 Minute N-13 and 2 Minute O-15 Gas Emissions from BLIP

Collider-Accelerator Department4-13-2010

Take 5 for Safety

Textbook Cone-Shaped Plume

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Short Stack and Lower Nearby Buildings – Wind Tunnel Simulation

Wake Effect from Building or Cone-shaped Hill

Cavity Zone Heat from ground

produces recirculation inside the cavity zone

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BLIP Building Looking North

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Inside BLIP

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Looking West From BLIP

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Looking South From BLIP

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North Side of BLIP Building

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North Side of BLIP Building Looking from “NSRL Valley”

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MicroR/h on April 6, 6 PM, 20 mm Water Path for Beam, 485 CFM, Routine Medical Production Targets, 117 MeV Beam

Radiation survey was performed at various outdoor locations around the following buildings/facilities:· NSRL, EBIS, HITL, REF, and LINAC· No readings above background were found in these

areas Outside wall of BLIP was 2000 microR/h near

cooling water pipe

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MicroR/h on April 7, 11 am, BLIP Off

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MicroR/h on April 8, 5 AM, South Wind, 65 mm Water Path, 485 CFM, 181 MeV Beam, Simos Targets Plus Normal BLIP Targets

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MicroR/h on April 8, 2 PM, South Wind, Reduced Water Path to 50 mm (25%) and Reduced Ventilation to 300 CFM (38%)

BLIP outside wall reduced from 8000 microR/h to 6000 microR/h (25%)

Area exposure rates dropped to 20 to 30 microR/h along the NSRL beam line, and 8 microR/h inside the NSRL building

Factor of 3 ± 1 reduction in NSRL area exposure rates

This met BNL criteria for less than 50 microR/h in uncontrolled areas, and C-AD HP requirement for less than 13 microR/h background to release NSRL targets

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MicroR/h on April 10, 2 PM, West Wind, Reduced Water Path to 50 mm and Reduced Ventilation to 300 CFM

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MicroR/h on April 12, 12:30 AM, North Wind, 50 mm Water Path, 300 CFM, 181 MeV

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Next Steps

Finish FY10 BLIP program with Simos targets and 50 mm or less water path and 300 CFM

Develop system to independently review modifications to BLIP targets and stack

Options:· Increase stack height· Minimize water path to 20 mm or less

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